title: Induced pluripotent stem (iPS) cells from human fetal stem cells (hFSCs).
abstract: BACKGROUND
  (1) Human embryonic stem (ES) cells are pluripotent but are difficult to be used for therapy because of immunological, oncological and ethical barriers. (2) Pluripotent cells exist in vivo, i.e., germ cells and epiblast cells but cannot be isolated without sacrificing the developing embryo. (3) Reprogramming to pluripotency is possible from adult cells using ectopic expression of OKSM and other integrative and non-integrative techniques. (4) Hurdles to overcome include i.e stability of the phenotype in relation to epigenetic memory.
  
  
  METHODS
  We reviewed the literature related to reprogramming, pluripotency and fetal stem cells.
  
  
  RESULTS
  (1) Fetal stem cells present some advantageous characteristics compared with their neonatal and postnatal counterparts, with regards to cell size, growth kinetics, and differentiation potential, as well as in vivo tissue repair capacity. (2) Amniotic fluid stem cells are more easily reprogrammed to pluripotency than adult fibroblast. (3) The parental population is heterogeneous and present an intermediate phenotype between ES and adult somatic stem cells, expressing markers of both.
  
  
  RESULTS
  (1) It is unclear whether induced pluripotent stem (iPS) derived from amniotic fluid stem cells are fully or partially reprogrammed. (2) Optimal protocols to ensure highest efficiency and phenotype stability remains to be determined. (3) The "level" of reprogramming, fully vs partial, of iPS derived from amniotic fluid stem cells remain to be determined.
  
  
  CONCLUSIONS
  Banking of fully reprogrammed cells may be important both for (1) autologous and allogenic applications in medicine, and (2) disease modeling.
authors.affiliation: Surgery Unit, Institute of Child Health, University College London and Great Ormond Street Hospital, London, UK. valentina.spinelli@unifi.it
authors.forename: Valentina
authors.initials: V
authors.lastname: Spinelli
authors.forename: Pascale V
authors.initials: PV
authors.lastname: Guillot
authors.forename: Paolo
authors.initials: P
authors.lastname: De Coppi
mesh_terms: D000653:Amniotic Fluid / Q000166:cytology; D000818:Animals; D065150:Cellular Reprogramming; D005260:Female; D053686:Fetal Stem Cells / Q000166:cytology*; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000166:cytology*; D010920:Placenta / Q000166:cytology; D011247:Pregnancy
keywords: Induced pluripotent stem cells; amniotic fluid stem cells; congenital malformation; fetal stem cells; haematopoietic stem cells; mesenchymal stem cells; placenta stem cells; pluripotency; reprogramming; umbilical cord stem cells